Multi-Scale finite element investigations into the flexural behavior of lightweight concrete beams partially reinforced with steel fiber

被引:1
作者
Esmaeili, Jamshid [1 ]
Ghaffarinia, Mahdi [1 ]
机构
[1] Univ Tabriz, Dept Civil Engn, Tabriz, Iran
关键词
center-point loading bending test; concrete notched beam; fiber reinforced concrete; lightweight concrete; multi-scale finite element model; residual flexural strength;
D O I
10.12989/cac.2022.29.6.393
中图分类号
TP39 [计算机的应用];
学科分类号
081203 ; 0835 ;
摘要
Lightweight concrete is a superior material due to its light weight and high strength. There however remain significant lacunae in engineering knowledge with regards to shear failure of lightweight fiber reinforced concrete beams. The main aim of the present study is to investigate the optimum usage of steel fibers in lightweight fiber reinforced concrete (LWFRC). Multi-scale finite element model calibrated with experimental results is developed to study the effect of steel fibers on the mechanical properties of LWFRC beams. To decrease the amount of steel fibers, it is preferred to reinforce only the middle section of the LWFRC beams, where the flexural stresses are higher. For numerical simulation, a multi-scale finite element model was developed. The cement matrix was modeled as homogeneous and uniform material and both steel fibers and lightweight coarse aggregates were randomly distributed within the matrix. Considering more realistic assumptions, the bonding between fibers and cement matrix was considered with the Cohesive Zone Model (CZM) and its parameters were determined using the model update method. Furthermore, conformity of Load-Crack Mouth Opening Displacement (CMOD) curves obtained from numerical modeling and experimental test results of notched beams under center-point loading tests were investigated. Validating the finite element model results with experimental tests, the effects of fibers??? volume fraction, and the length of the reinforced middle section, on flexural and residual strengths of LWFRC, were studied. Results indicate that using steel fibers in a specified length of the concrete beam with high flexural stresses, and considerable savings can be achieved in using steel fibers. Reducing the length of the reinforced middle section from 50 to 30 cm in specimens containing 10 kg/m3 of steel fibers, resulting in a considerable decrease of the used steel fibers by four times, whereas only a 7% reduction in bearing capacity was observed. Therefore, determining an appropriate length of the reinforced middle section is an essential parameter in reducing fibers, usage leading to more affordable construction costs.
引用
收藏
页码:393 / 405
页数:13
相关论文
共 26 条
[1]   Investigating the mechanical and microstructure properties of fibre-reinforced lightweight concrete under elevated temperatures [J].
Amin, Mohamed ;
Tayeh, Bassam A. ;
agwa, Ibrahim saad .
CASE STUDIES IN CONSTRUCTION MATERIALS, 2020, 13
[2]  
[Anonymous], 2018, C33C33M ASMT
[3]  
[Anonymous], 2002, MATER STRUCT, V35, P579, DOI [10.1617/14007, DOI 10.1617/13884, 10.1617/13884]
[4]  
[Anonymous], 2014, C330C330M ASMT
[5]  
[Anonymous], 2019, C1609C1609M ASMT
[6]   Fiber synergy in Hybrid Fiber Reinforced Concrete (HyFRC) in flexure and direct shear [J].
Banthia, N. ;
Majdzadeh, F. ;
Wu, J. ;
Bindiganavile, V. .
CEMENT & CONCRETE COMPOSITES, 2014, 48 :91-97
[7]  
Chang TP, 1996, ACI MATER J, V93, P3
[8]   Effect of expanded polystyrene on the flexural behavior of lightweight glass fiber reinforced cement [J].
Cheng, Congmi ;
Hong, Silei ;
Zhang, Yafang ;
He, Juan .
CONSTRUCTION AND BUILDING MATERIALS, 2020, 265
[9]   Mesoscale computational modeling of the mechanical behavior of cement composite materials [J].
Congro, Marcello ;
Roehl, Deane ;
Mejia, Cristian .
COMPOSITE STRUCTURES, 2021, 257
[10]  
Du X., 2021, METHODOLOGY MESOSCAL